<!DOCTYPE html>
<html lang="en"><head>
  <meta charset="utf-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1"><!-- Begin Jekyll SEO tag v2.8.0 -->
<title>0035: Dialogs I - The About Dialog | gtkDcoding</title>
<meta name="generator" content="Jekyll v4.3.4" />
<meta property="og:title" content="0035: Dialogs I - The About Dialog" />
<meta name="author" content="Ron Tarrant" />
<meta property="og:locale" content="en_US" />
<meta name="description" content="How to use a GTK AboutDialog - a D-language tutorial." />
<meta property="og:description" content="How to use a GTK AboutDialog - a D-language tutorial." />
<link rel="canonical" href="http://localhost:4000/posts/0035-help-about-dialog.html" />
<meta property="og:url" content="http://localhost:4000/posts/0035-help-about-dialog.html" />
<meta property="og:site_name" content="gtkDcoding" />
<meta property="og:type" content="article" />
<meta property="article:published_time" content="2019-05-14T00:00:00-04:00" />
<meta name="twitter:card" content="summary" />
<meta property="twitter:title" content="0035: Dialogs I - The About Dialog" />
<script type="application/ld+json">
{"@context":"https://schema.org","@type":"BlogPosting","author":{"@type":"Person","name":"Ron Tarrant"},"dateModified":"2019-05-14T00:00:00-04:00","datePublished":"2019-05-14T00:00:00-04:00","description":"How to use a GTK AboutDialog - a D-language tutorial.","headline":"0035: Dialogs I - The About Dialog","mainEntityOfPage":{"@type":"WebPage","@id":"http://localhost:4000/posts/0035-help-about-dialog.html"},"url":"http://localhost:4000/posts/0035-help-about-dialog.html"}</script>
<!-- End Jekyll SEO tag -->
<link rel="stylesheet" href="../assets/main.css">
  <link rel="stylesheet" href="../css/style.css" /><link type="application/atom+xml" rel="alternate" href="http://localhost:4000/feed.xml" title="gtkDcoding" /></head>
<body><header class="site-header" role="banner">

  <div class="wrapper"><a class="site-title" rel="author" href="../">gtkDcoding</a><nav class="site-nav">
        <input type="checkbox" id="nav-trigger" class="nav-trigger" />
        <label for="nav-trigger">
          <span class="menu-icon">
            <svg viewBox="0 0 18 15" width="18px" height="15px">
              <path d="M18,1.484c0,0.82-0.665,1.484-1.484,1.484H1.484C0.665,2.969,0,2.304,0,1.484l0,0C0,0.665,0.665,0,1.484,0 h15.032C17.335,0,18,0.665,18,1.484L18,1.484z M18,7.516C18,8.335,17.335,9,16.516,9H1.484C0.665,9,0,8.335,0,7.516l0,0 c0-0.82,0.665-1.484,1.484-1.484h15.032C17.335,6.031,18,6.696,18,7.516L18,7.516z M18,13.516C18,14.335,17.335,15,16.516,15H1.484 C0.665,15,0,14.335,0,13.516l0,0c0-0.82,0.665-1.483,1.484-1.483h15.032C17.335,12.031,18,12.695,18,13.516L18,13.516z"/>
            </svg>
          </span>
        </label>

        <div class="trigger"><a class="page-link" href="../about.html">About</a><a class="page-link" href="../index-reverse.html">Posts in Date Order</a><a class="page-link" href="../topics.html">Blog Posts by Topic</a></div>
      </nav></div>
</header>
<main class="page-content" aria-label="Content">
      <div class="wrapper">
        <article class="post h-entry" itemscope itemtype="http://schema.org/BlogPosting">
	<header class="post-header">
		<link rel="stylesheet" href="../css/font_size.css" />
		<link rel="stylesheet" href="../css/figure.css" />
		<link rel="stylesheet" href="../css/topics/dialog.css" />  <!-- sub in the tag/topic -->
		<link rel="stylesheet" href="../css/modal.css" />
		<link rel="stylesheet" href="../css/post.css" />
		<link rel="stylesheet" href="../css/mascot_effects.css" />

		
		
		<p class="post-meta">
		<time class="dt-published" datetime="2019-05-14T00:00:00-04:00" itemprop="datePublished">Tuesday, May 14, 2019
		</time>• by <span itemprop="author" itemscope itemtype="http://schema.org/Person"><span class="p-author h-card" itemprop="name">Ron Tarrant</span></span></p>
	</header>

	<div class="post-content e-content" itemprop="articleBody">
		<div class="skew-line"></div>
		<h2 id="0035-dialogs-i---the-about-dialog">0035: Dialogs I - The About Dialog</h2>

<div class="screenshot-frame">
	<div class="frame-header">
		Results of this example:
	</div>
	<div class="frame-screenshot">
		<figure>
			<img id="img0" src="../images/screenshots/013_dialogs/dialog_01.png" alt="Current example output" />		<!-- img# -->
			
			<!-- Modal for screenshot -->
			<div id="modal0" class="modal">																	<!-- modal# -->
				<span class="close0">&times;</span>															<!-- close# -->
				<img class="modal-content" id="img00" />															<!-- img## -->
				<div id="caption"></div>
			</div>
			
			<script>
			// Get the modal
			var modal = document.getElementById("modal0");														// modal#
			
			// Get the image and insert it inside the modal - use its "alt" text as a caption
			var img = document.getElementById("img0");															// img#
			var modalImg = document.getElementById("img00");													// img##
			var captionText = document.getElementById("caption");

			img.onclick = function()
			{
			  modal.style.display = "block";
			  modalImg.src = this.src;
			  captionText.innerHTML = this.alt;
			}
			
			// Get the <span> element that closes the modal
			var span = document.getElementsByClassName("close0")[0];											// close#
			
			// When the user clicks on <span> (x), close the modal
			span.onclick = function()
			{ 
				modal.style.display = "none";
			}
			</script>
			<figcaption>
			Current example output
			</figcaption>
		</figure>
	</div>

	<div class="frame-terminal">
		<figure class="right">
			<img id="img1" src="../images/screenshots/013_dialogs/dialog_01_term.png" alt="Current example terminal output" />		<!-- img#, filename -->

			<!-- Modal for terminal shot -->
			<div id="modal1" class="modal">																				<!-- modal# -->
				<span class="close1">&times;</span>																		<!-- close# -->
				<img class="modal-content" id="img11" />																		<!-- img## -->
				<div id="caption"></div>
			</div>
			
			<script>
			// Get the modal
			var modal = document.getElementById("modal1");																	// modal#
			
			// Get the image and insert it inside the modal - use its "alt" text as a caption
			var img = document.getElementById("img1");																		// img#
			var modalImg = document.getElementById("img11");																// img##
			var captionText = document.getElementById("caption");

			img.onclick = function()
			{
			  modal.style.display = "block";
			  modalImg.src = this.src;
			  captionText.innerHTML = this.alt;
			}
			
			// Get the <span> element that closes the modal
			var span = document.getElementsByClassName("close1")[0];														// close#
			
			// When the user clicks on <span> (x), close the modal
			span.onclick = function()
			{ 
				modal.style.display = "none";
			}
			</script>

			<figcaption>
				Current example terminal output (click for enlarged view)
			</figcaption>
		</figure>
	</div>

	<div class="frame-footer">																								<!-- ------------- filename (below) --------- -->
		The code file for this example is available <a href="https://github.com/rontarrant/gtkd_demos/blob/master/013_dialogs/dialog_01_help_about.d" target="_blank">here</a>.
	</div>
</div>

<p>Starting today, and for the next few weeks, we’ll be looking at <code class="language-plaintext highlighter-rouge">Dialog</code> windows of various types. We’ll get started with one of the simpler ones, the AboutDialog, but to make it more interesting, we’ll toss in a <code class="language-plaintext highlighter-rouge">Pixbuf</code>.</p>

<p>Let’s get going by checking out…</p>

<h3 id="the-imports">The Imports</h3>

<p>These are the ones we haven’t worked with yet:</p>

<div class="language-d highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="k">import</span> <span class="n">gtk</span><span class="p">.</span><span class="n">AboutDialog</span><span class="p">;</span>
<span class="k">import</span> <span class="n">gdk</span><span class="p">.</span><span class="n">Pixbuf</span><span class="p">;</span>
</code></pre></div></div>

<p>Okay… <code class="language-plaintext highlighter-rouge">main()</code> is the same and we’ve seen <code class="language-plaintext highlighter-rouge">TestRigWindow</code> more than 30 times, and these aren’t new, either:</p>

<ul>
  <li><code class="language-plaintext highlighter-rouge">AppBox</code>,</li>
  <li><code class="language-plaintext highlighter-rouge">MyMenuBar</code>,</li>
  <li><code class="language-plaintext highlighter-rouge">HelpHeader</code> (except for the name, anyway), and</li>
  <li><code class="language-plaintext highlighter-rouge">HelpMenu</code>.</li>
</ul>

<p>And that brings us to…</p>

<h3 id="the-aboutitem">The AboutItem</h3>

<p>We have a ton of string tied around the initialization section and maybe that’s so the other stray items don’t wander off:</p>

<div class="language-d highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="nb">string</span> <span class="n">itemLabel</span> <span class="p">=</span> <span class="s">"About"</span><span class="p">;</span>
<span class="nb">string</span> <span class="n">sectionName</span> <span class="p">=</span> <span class="s">"Them What Done Stuff"</span><span class="p">;</span>
<span class="nb">string</span><span class="p">[]</span> <span class="n">people</span> <span class="p">=</span> <span class="p">[</span><span class="s">"Laurence Find"</span><span class="p">,</span> <span class="s">"Jerome Hayward"</span><span class="p">,</span> <span class="s">"Dick van Puddlesopper"</span><span class="p">];</span>
<span class="nb">string</span><span class="p">[]</span> <span class="n">artists</span> <span class="p">=</span> <span class="p">[</span><span class="s">"Alice Warhol"</span><span class="p">,</span> <span class="s">"Salvador Deli"</span><span class="p">,</span> <span class="s">"My Brother-in-law, Bill"</span><span class="p">];</span>
<span class="nb">string</span> <span class="n">comments</span> <span class="p">=</span> <span class="s">"This is a fine bit of software built for the rigors of testing dialog windows."</span><span class="p">;</span>
<span class="nb">string</span><span class="p">[]</span> <span class="n">documenters</span> <span class="p">=</span> <span class="p">[</span><span class="s">"Billy Buck Thorndyke"</span><span class="p">,</span> <span class="s">"Phil Gates"</span><span class="p">];</span>
<span class="nb">string</span> <span class="n">license</span> <span class="p">=</span> <span class="s">"This is a FOSS Budget build of a GNOLD project"</span><span class="p">;</span>
<span class="nb">string</span> <span class="n">programName</span> <span class="p">=</span> <span class="s">"About Dialog Demo"</span><span class="p">;</span>
<span class="nb">string</span> <span class="n">protection</span> <span class="p">=</span> <span class="s">"Copywrong 2019 © The Three Stool Pigeons"</span><span class="p">;</span>
<span class="n">Pixbuf</span> <span class="n">logoPixbuf</span><span class="p">;</span>
<span class="nb">string</span> <span class="n">pixbufFilename</span> <span class="p">=</span> <span class="s">"images/logo.png"</span><span class="p">;</span>
<span class="n">Window</span> <span class="n">parentWindow</span><span class="p">;</span>
<span class="n">AboutDialog</span> <span class="n">aboutDialog</span><span class="p">;</span>
</code></pre></div></div>

<p>You could probably leave most of these strings empty, especially if you don’t work with a team, but I filled all these in for demonstration purposes.</p>

<p>But as I breezed through that list of classes that hadn’t changed, there actually was one change worth mentioning…</p>

<h4 id="passing-down-the-window">Passing Down the Window</h4>

<p>Because the <code class="language-plaintext highlighter-rouge">AboutDialog</code> (or any other dialog) needs to know who its mommy is, we gotta give it an ersatz family tree, passing down the <code class="language-plaintext highlighter-rouge">Window</code> pointer so when the <code class="language-plaintext highlighter-rouge">Dialog</code> goes up, it can go <code class="language-plaintext highlighter-rouge">MODAL</code> if it needs to. If you take a quick look through the code, you’ll see this is done very much the same way we passed along the <code class="language-plaintext highlighter-rouge">AccelGroup</code> in Blog Post #32 - <a href="./0032-accelerator-keys.html">Adding Accelerator Keys to MenuItems</a>.</p>

<p><em>Note: if you want your <code class="language-plaintext highlighter-rouge">Dialog</code> to be <code class="language-plaintext highlighter-rouge">MODAL</code>, use <code class="language-plaintext highlighter-rouge">DialogFlags.MODAL</code> which can be found in <code class="language-plaintext highlighter-rouge">generated/gtkd/gtk/c/types.d</code>.</em></p>

<h3 id="hooking-up-the-menuitem">Hooking up the MenuItem</h3>

<p>In the constructor, we do this:</p>

<div class="language-d highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="k">this</span><span class="p">(</span><span class="n">Window</span> <span class="n">extParentWindow</span><span class="p">)</span>
<span class="p">{</span>
	<span class="k">super</span><span class="p">(</span><span class="n">itemLabel</span><span class="p">);</span>
	<span class="n">addOnActivate</span><span class="p">(&amp;</span><span class="n">doSomething</span><span class="p">);</span>
	<span class="n">parentWindow</span> <span class="p">=</span> <span class="n">extParentWindow</span><span class="p">;</span>
	
<span class="p">}</span> <span class="c1">// this()</span>
</code></pre></div></div>

<p>Like any other <code class="language-plaintext highlighter-rouge">MenuItem</code>, we instantiate and hook up the callback, but then we have one more step. We assign the local pointer to the parent Window so we can use it in the callback.</p>

<p>The callback is quite busy:</p>

<div class="language-d highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="kt">void</span> <span class="n">doSomething</span><span class="p">(</span><span class="n">MenuItem</span> <span class="n">mi</span><span class="p">)</span>
<span class="p">{</span>
	<span class="kt">int</span> <span class="n">responseID</span><span class="p">;</span>
	
	<span class="n">writeln</span><span class="p">(</span><span class="s">"Bringing up dialog..."</span><span class="p">);</span>
	
	<span class="n">logoPixbuf</span> <span class="p">=</span> <span class="k">new</span> <span class="n">Pixbuf</span><span class="p">(</span><span class="n">pixbufFilename</span><span class="p">);</span>
	
	<span class="c1">// Although it seems we should do all this config stuff in this()</span>
	<span class="c1">// it has to be done here.</span>
	<span class="n">AboutDialog</span> <span class="n">aboutDialog</span> <span class="p">=</span> <span class="k">new</span> <span class="n">AboutDialog</span><span class="p">();</span>
	<span class="n">aboutDialog</span><span class="p">.</span><span class="n">setAuthors</span><span class="p">(</span><span class="n">people</span><span class="p">);</span>
	<span class="n">aboutDialog</span><span class="p">.</span><span class="n">setArtists</span><span class="p">(</span><span class="n">artists</span><span class="p">);</span>
	<span class="n">aboutDialog</span><span class="p">.</span><span class="n">addCreditSection</span><span class="p">(</span><span class="n">sectionName</span><span class="p">,</span> <span class="n">people</span><span class="p">);</span> <span class="c1">// shows when the Credits button is clicked</span>
	<span class="n">aboutDialog</span><span class="p">.</span><span class="n">setCopyright</span><span class="p">(</span><span class="n">protection</span><span class="p">);</span>
	<span class="n">aboutDialog</span><span class="p">.</span><span class="n">setArtists</span><span class="p">(</span><span class="n">artists</span><span class="p">);</span>
	<span class="n">aboutDialog</span><span class="p">.</span><span class="n">setComments</span><span class="p">(</span><span class="n">comments</span><span class="p">);</span>
	<span class="n">aboutDialog</span><span class="p">.</span><span class="n">setLicense</span><span class="p">(</span><span class="n">license</span><span class="p">);</span>
	<span class="n">aboutDialog</span><span class="p">.</span><span class="n">setProgramName</span><span class="p">(</span><span class="n">programName</span><span class="p">);</span>
	<span class="n">aboutDialog</span><span class="p">.</span><span class="n">setLogo</span><span class="p">(</span><span class="n">logoPixbuf</span><span class="p">);</span>
	<span class="n">aboutDialog</span><span class="p">.</span><span class="n">setTransientFor</span><span class="p">(</span><span class="n">parentWindow</span><span class="p">);</span>
	
	<span class="n">aboutDialog</span><span class="p">.</span><span class="n">run</span><span class="p">();</span>
	<span class="n">aboutDialog</span><span class="p">.</span><span class="n">destroy</span><span class="p">();</span>
	
<span class="p">}</span> <span class="c1">// doSomething()</span>
</code></pre></div></div>

<p>We need a <code class="language-plaintext highlighter-rouge">responseID</code> for any dialog, even if we ignore it like we do here. As we move deeper into dialogs, we’ll come back to this variable and look at it more closely.</p>

<p>And there’s the <code class="language-plaintext highlighter-rouge">Pixbuf</code> I mentioned. Here, it’s used to show off the gtkDcoding logo.</p>

<p>Then we instantiate the dialog:</p>

<div class="language-plaintext highlighter-rouge"><div class="highlight"><pre class="highlight"><code>AboutDialog aboutDialog = new AboutDialog();
</code></pre></div></div>

<p>Fill in all the fields:</p>

<div class="language-d highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="n">aboutDialog</span><span class="p">.</span><span class="n">setArtists</span><span class="p">(</span><span class="n">artists</span><span class="p">);</span>
<span class="n">aboutDialog</span><span class="p">.</span><span class="n">setAuthors</span><span class="p">(</span><span class="n">people</span><span class="p">);</span>
<span class="n">aboutDialog</span><span class="p">.</span><span class="n">setComments</span><span class="p">(</span><span class="n">comments</span><span class="p">);</span>
<span class="n">aboutDialog</span><span class="p">.</span><span class="n">setCopyright</span><span class="p">(</span><span class="n">protection</span><span class="p">);</span>
<span class="n">aboutDialog</span><span class="p">.</span><span class="n">setDocumenters</span><span class="p">(</span><span class="n">documenters</span><span class="p">);</span>
<span class="n">aboutDialog</span><span class="p">.</span><span class="n">setLicense</span><span class="p">(</span><span class="n">license</span><span class="p">);</span>
<span class="n">aboutDialog</span><span class="p">.</span><span class="n">setLicenseType</span><span class="p">(</span><span class="n">licenseType</span><span class="p">);</span>
<span class="n">aboutDialog</span><span class="p">.</span><span class="n">addCreditSection</span><span class="p">(</span><span class="n">sectionName</span><span class="p">,</span> <span class="n">people</span><span class="p">);</span> <span class="c1">// shows when the Credits button is clicked</span>
<span class="n">aboutDialog</span><span class="p">.</span><span class="n">setProgramName</span><span class="p">(</span><span class="n">programName</span><span class="p">);</span>
<span class="n">aboutDialog</span><span class="p">.</span><span class="n">setLogo</span><span class="p">(</span><span class="n">logoPixbuf</span><span class="p">);</span>
<span class="n">aboutDialog</span><span class="p">.</span><span class="n">setLogoIconName</span><span class="p">(</span><span class="n">logoIconName</span><span class="p">);</span>
<span class="n">aboutDialog</span><span class="p">.</span><span class="n">setVersion</span><span class="p">(</span><span class="n">productVersion</span><span class="p">);</span>
<span class="n">aboutDialog</span><span class="p">.</span><span class="n">setWebsite</span><span class="p">(</span><span class="n">website</span><span class="p">);</span>
<span class="n">aboutDialog</span><span class="p">.</span><span class="n">setWebsiteLabel</span><span class="p">(</span><span class="n">websiteLabel</span><span class="p">);</span>
<span class="n">aboutDialog</span><span class="p">.</span><span class="n">setTransientFor</span><span class="p">(</span><span class="n">parentWindow</span><span class="p">);</span>
</code></pre></div></div>

<p><em>Note: There may be a bug in</em> GTK <em>that (apparently) stops the website link from working with some operating systems.</em> Mac <em>was mentioned as one that falls victim to this, but it does work with Windows (it does, however, spit out a warning). I haven’t tried it with</em> Linux.</p>

<p>And finally, we open it:</p>

<div class="language-d highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="n">aboutDialog</span><span class="p">.</span><span class="n">run</span><span class="p">();</span>
</code></pre></div></div>

<p>And the last statement doesn’t get called until the dialog closes and program control comes back to this object (the <code class="language-plaintext highlighter-rouge">AboutMenuItem</code> object):</p>

<div class="language-d highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="n">aboutDialog</span><span class="p">.</span><span class="n">destroy</span><span class="p">();</span>
</code></pre></div></div>

<p>All this does is destroy everything we built. And if the <code class="language-plaintext highlighter-rouge">Dialog</code> gets opened again? The entire dialog is rebuilt from scratch.</p>

<h2 id="conclusion">Conclusion</h2>

<p>And that was a quick look at a simple <code class="language-plaintext highlighter-rouge">Dialog</code>. As we go along, things could get complicated, especially when we dig into rolling our own dialog from scratch. Now, that will be an adventure.</p>

<p>Until next time… bye.</p>

<div class="blog-nav">
	<div style="float: left;">
		<a href="./0034-accelgroup-singleton.html">Previous: AccelGroup Singleton</a>
	</div>
	<div style="float: right;">
		<a href="./0036-file-open-dialogs.html">Next: Open File Dialog</a>
	</div>
</div>
<p>
	<h3></h3>
<div class="inpage-frame">
	<a href="https://github.com/sponsors/rontarrant">
		<BR>
		<BR>
		<B>Is this article useful? Educational? Entertaining, perhaps?</B>
		<BR>
		<figure class="left">
			<img src="../images/favorite_32.png" alt="Sponsorship heart" style="width: 32px; height: 32px;">
		</figure>
		You're free to accept or decline this invitation to become our newest sponsor.
	</a>
</div>
	<h4 class="comment-blurb"><B>Comments? Questions? Observations?</B></h4>
	<p>
		Did we miss a tidbit of information that would make this post even more informative? Let's talk about it in the comments.
	</p>
	<script src="https://utteranc.es/client.js"
		repo="rontarrant"
		issue-term="pathname"
		theme="github-light"
		crossorigin="anonymous"
		async>
	</script>
	<ul>
		<li> come on over to the <a href="https://forum.dlang.org/">D Language Forum</a> and look for one of the <i>gtkDcoding</i> announcement posts, </li>
		<li> drop by <a href="https://forum.gtkd.org/">the <i>GtkD Forum</i></a>,</li>
		<li> follow the link below to email me, or</li>
		<li> go to the	<a href="https://www.facebook.com">gtkDcoding Facebook page.</a></li>
	</ul>
</p>
<p> You can also subscribe <a href="/feed.xml">via RSS</a> so you won't miss anything. Thank you very much for dropping by.</p>
<p>&copy; Copyright 2025 Ron Tarrant </p>
</div>

	<a class="u-url" href="./0035-help-about-dialog.html" hidden></a>
</article>

      </div>
    </main><footer class="site-footer h-card">
  <data class="u-url" href="/"></data>

  <div class="wrapper">

    <h2 class="footer-heading">gtkDcoding</h2>

    <div class="footer-col-wrapper">
      <div class="footer-col footer-col-1">
        <ul class="contact-list">
          <li class="p-name">Ron Tarrant</li><li><a class="u-email" href="mailto:gtkDcoding@gmail.com">gtkDcoding@gmail.com</a></li></ul>
      </div>

      <div class="footer-col footer-col-2"><ul class="social-media-list"><li><a href="https://github.com/rontarrant"><svg class="svg-icon"><use xlink:href="../assets/minima-social-icons.svg#github"></use></svg> <span class="username">rontarrant</span></a></li></ul>
</div>

      <div class="footer-col footer-col-3">
        <p>Simple examples of how to use GtkD to build GUI applications.</p>
      </div>
    </div>

  </div>

</footer>
</body>

</html>
